1. Field of the Invention
This invention relates to a metal substrate apparatus for a transfer mold-type IC card module used in manufacturing non-contact IC cards, a manufacturing method for a transfer mold-type IC card module apparatus used in manufacturing non-contact IC cards with the said metal substrate, and an IC card module apparatus.
2. Background Art
IC card technology continues to spread gradually due to the need for protecting the privacy of information. In recent years, there have been proposed non-contact IC cards which can send and receive information without contact with a device for reading and writing information (reader-writer). Among the proposed IC cards, those which use electromagnetic waves to exchange signals with an outside reader-writer, or exchange signals and supply power, have been practically developed.
FIGS. 8(a), 8(b) show an example of one of these non-contact IC cards. FIG. 8(a) shows an IC module 812 connected to an antenna 811. FIG. 8(b) illustrates the typical circuit structure of such a card.
In FIGS. 8(a) and 8(b), the IC card 810 has the antenna 811, the IC module 812, and a terminal 813 (of the IC module).
With regard to the loading on an IC chip on this type of IC module, the most commonly used mounting method is COB (Chip on Board), where the IC chip is loaded onto a print board and connected to the print board by a bonding wire. The drawback to this method is that the mounting thickness cannot be reduced. Recently, a separate mounting method has been proposed in which the mounting thickness can be reduced and mass production is possible. In this method, an IC chip is mounted on a die pad of a half-etched metal substrate, and connected to terminals of the metal substrate by a bonding wire.
In an IC module formed in this manner, a single metal substrate has various regions after its processing material is processed, including a region where the IC chip is loaded (die pad), a region for connection with the antenna circuits, and a region for input and output terminals. The metal substrate is separated and formed when parts of these regions are connected. When forming the IC module, these regions are connected to the processing material via connecting parts, so that a plurality of individual metal substrates are attached to the processing material. After IC chips are loaded onto the individual metal substrates, the metal substrates are sealed with sealing resin and cut and separated at prescribed connecting parts.
In some cases, an individual metal substrate is called a lead or a lead frame. The device is called a lead frame when a plurality of individual metal substrates are attached directly to the processing material or to a frame and connecting parts connected.
When such a metal substrate is formed by pressing, burrs 911 may be formed during pressing. As shown in FIG. 9(a), if the metal substrate has been resin-sealed, resin leakage 931 can occur through the rear side. The etching method is adopted to avoid these problems. FIG. 9(b) shows that through the etching method, no resin leakage occurs in the sealing process.
In FIGS. 9(a) and 9(b), there are shown a metal substrate 910, IC chip 920, sealing resin 930, resin leakage 931, and bonding wire 940.
With regard to the etching method, a thin Cu material or 42 alloy (42% Ni—Fe alloy) may be used for the processing material. In addition, the conventional reel-to-reel method (reel method) may be used for the plate processing and etching.
Following the etching of the processing material and the attachment of the metal substrate on the surface of the processing material, the processing material then undergoes plating, with either some parts plated in silver and other in palladium or the entire material plated in palladium, followed by mounting of the IC chips, wire bonding, and resin sealing for each metal substrate. These processes are carried out consecutively or divided into different stages and carried out by the reel method.
Conventionally, in the etching of the processing material, when manufacturing the metal substrates for the IC module by the reel method after attaching them to the processing material, the metal substrates are arranged and manufactured one-by-one such that they do not overlap, as shown in FIG. 7(a).
FIG. 7(b) shows the metal substrate of FIG. 7(a) after being loaded with an IC chip in a die pad 621 and sealed with sealing resin by the transfer method.
Thereafter, an IC card module is obtained by cutting at prescribed lines.
In FIGS. 7(a) and 7(b), the parts represented are the processing material 611, individual metal substrate 620, die pad 621, half-etching part 621H, terminals 622A and 622B (to connect to the antennas), through-hole 625, connecting part 626, sprocket 628, and sealing resin 640.
The foregoing conventional metal substrate manufacturing method is described in JP Laid-Open Publication 2000-174176.
As described above, there is known a metal substrate for use in an IC module, wherein an etching process is carried out on a processing material, and a metal substrate for an IC module is attached to the surface of the processing material, the metal substrate being further processed by the reel method. In this case, an IC module for non-contact-type IC cards must be mass-producible at a low cost.